layer.h revision 58537e28ecd584eab876aee8be7156509866d23a 
1// Copyright 2010 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef CC_LAYERS_LAYER_H_
6#define CC_LAYERS_LAYER_H_
7
8#include <set>
9#include <string>
10
11#include "base/callback.h"
12#include "base/memory/ref_counted.h"
13#include "base/observer_list.h"
14#include "cc/animation/layer_animation_controller.h"
15#include "cc/animation/layer_animation_value_observer.h"
16#include "cc/base/cc_export.h"
17#include "cc/base/region.h"
18#include "cc/base/scoped_ptr_vector.h"
19#include "cc/layers/compositing_reasons.h"
20#include "cc/layers/draw_properties.h"
21#include "cc/layers/layer_lists.h"
22#include "cc/layers/layer_position_constraint.h"
23#include "cc/layers/paint_properties.h"
24#include "cc/layers/render_surface.h"
25#include "cc/output/filter_operations.h"
26#include "cc/trees/occlusion_tracker.h"
27#include "skia/ext/refptr.h"
28#include "third_party/skia/include/core/SkColor.h"
29#include "third_party/skia/include/core/SkImageFilter.h"
30#include "third_party/skia/include/core/SkPicture.h"
31#include "ui/gfx/rect.h"
32#include "ui/gfx/rect_f.h"
33#include "ui/gfx/transform.h"
34
35namespace gfx {
36class BoxF;
37}
38
39namespace cc {
40
41class Animation;
42class AnimationDelegate;
43struct AnimationEvent;
44class CopyOutputRequest;
45class LayerAnimationDelegate;
46class LayerAnimationEventObserver;
47class LayerClient;
48class LayerImpl;
49class LayerTreeHost;
50class LayerTreeImpl;
51class PriorityCalculator;
52class RenderingStatsInstrumentation;
53class ResourceUpdateQueue;
54class ScrollbarLayerInterface;
55struct AnimationEvent;
56
57// Base class for composited layers. Special layer types are derived from
58// this class.
59class CC_EXPORT Layer : public base::RefCounted<Layer>,
60                        public LayerAnimationValueObserver {
61 public:
62  enum LayerIdLabels {
63    INVALID_ID = -1,
64  };
65
66  static scoped_refptr<Layer> Create();
67
68  int id() const { return layer_id_; }
69
70  Layer* RootLayer();
71  Layer* parent() { return parent_; }
72  const Layer* parent() const { return parent_; }
73  void AddChild(scoped_refptr<Layer> child);
74  void InsertChild(scoped_refptr<Layer> child, size_t index);
75  void ReplaceChild(Layer* reference, scoped_refptr<Layer> new_layer);
76  void RemoveFromParent();
77  void RemoveAllChildren();
78  void SetChildren(const LayerList& children);
79  bool HasAncestor(const Layer* ancestor) const;
80
81  const LayerList& children() const { return children_; }
82  Layer* child_at(size_t index) { return children_[index].get(); }
83
84  // This requests the layer and its subtree be rendered and given to the
85  // callback. If the copy is unable to be produced (the layer is destroyed
86  // first), then the callback is called with a NULL/empty result.
87  void RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> request);
88  bool HasCopyRequest() const {
89    return !copy_requests_.empty();
90  }
91
92  void SetAnchorPoint(gfx::PointF anchor_point);
93  gfx::PointF anchor_point() const { return anchor_point_; }
94
95  void SetAnchorPointZ(float anchor_point_z);
96  float anchor_point_z() const { return anchor_point_z_; }
97
98  virtual void SetBackgroundColor(SkColor background_color);
99  SkColor background_color() const { return background_color_; }
100  // If contents_opaque(), return an opaque color else return a
101  // non-opaque color.  Tries to return background_color(), if possible.
102  SkColor SafeOpaqueBackgroundColor() const;
103
104  // A layer's bounds are in logical, non-page-scaled pixels (however, the
105  // root layer's bounds are in physical pixels).
106  void SetBounds(gfx::Size bounds);
107  gfx::Size bounds() const { return bounds_; }
108
109  void SetMasksToBounds(bool masks_to_bounds);
110  bool masks_to_bounds() const { return masks_to_bounds_; }
111
112  void SetMaskLayer(Layer* mask_layer);
113  Layer* mask_layer() { return mask_layer_.get(); }
114  const Layer* mask_layer() const { return mask_layer_.get(); }
115
116  virtual void SetNeedsDisplayRect(const gfx::RectF& dirty_rect);
117  void SetNeedsDisplay() { SetNeedsDisplayRect(gfx::RectF(bounds())); }
118
119  void SetOpacity(float opacity);
120  float opacity() const { return opacity_; }
121  bool OpacityIsAnimating() const;
122  virtual bool OpacityCanAnimateOnImplThread() const;
123
124  void SetFilters(const FilterOperations& filters);
125  const FilterOperations& filters() const { return filters_; }
126
127  void SetFilter(const skia::RefPtr<SkImageFilter>& filter);
128  skia::RefPtr<SkImageFilter> filter() const { return filter_; }
129
130  // Background filters are filters applied to what is behind this layer, when
131  // they are viewed through non-opaque regions in this layer. They are used
132  // through the WebLayer interface, and are not exposed to HTML.
133  void SetBackgroundFilters(const FilterOperations& filters);
134  const FilterOperations& background_filters() const {
135    return background_filters_;
136  }
137
138  virtual void SetContentsOpaque(bool opaque);
139  bool contents_opaque() const { return contents_opaque_; }
140
141  void SetPosition(gfx::PointF position);
142  gfx::PointF position() const { return position_; }
143
144  void SetIsContainerForFixedPositionLayers(bool container);
145  bool IsContainerForFixedPositionLayers() const;
146
147  void SetPositionConstraint(const LayerPositionConstraint& constraint);
148  const LayerPositionConstraint& position_constraint() const {
149    return position_constraint_;
150  }
151
152  void SetSublayerTransform(const gfx::Transform& sublayer_transform);
153  const gfx::Transform& sublayer_transform() const {
154    return sublayer_transform_;
155  }
156
157  void SetTransform(const gfx::Transform& transform);
158  const gfx::Transform& transform() const { return transform_; }
159  bool TransformIsAnimating() const;
160
161  void SetScrollParent(Layer* parent);
162
163  Layer* scroll_parent() { return scroll_parent_; }
164  const Layer* scroll_parent() const { return scroll_parent_; }
165
166  void AddScrollChild(Layer* child);
167  void RemoveScrollChild(Layer* child);
168
169  std::set<Layer*>* scroll_children() { return scroll_children_.get(); }
170  const std::set<Layer*>* scroll_children() const {
171    return scroll_children_.get();
172  }
173
174  void SetClipParent(Layer* ancestor);
175
176  Layer* clip_parent() { return clip_parent_; }
177  const Layer* clip_parent() const {
178    return clip_parent_;
179  }
180
181  void AddClipChild(Layer* child);
182  void RemoveClipChild(Layer* child);
183
184  std::set<Layer*>* clip_children() { return clip_children_.get(); }
185  const std::set<Layer*>* clip_children() const {
186    return clip_children_.get();
187  }
188
189  DrawProperties<Layer, RenderSurface>& draw_properties() {
190    return draw_properties_;
191  }
192  const DrawProperties<Layer, RenderSurface>& draw_properties() const {
193    return draw_properties_;
194  }
195
196  // The following are shortcut accessors to get various information from
197  // draw_properties_
198  const gfx::Transform& draw_transform() const {
199    return draw_properties_.target_space_transform;
200  }
201  const gfx::Transform& screen_space_transform() const {
202    return draw_properties_.screen_space_transform;
203  }
204  float draw_opacity() const { return draw_properties_.opacity; }
205  bool draw_opacity_is_animating() const {
206    return draw_properties_.opacity_is_animating;
207  }
208  bool draw_transform_is_animating() const {
209    return draw_properties_.target_space_transform_is_animating;
210  }
211  bool screen_space_transform_is_animating() const {
212    return draw_properties_.screen_space_transform_is_animating;
213  }
214  bool screen_space_opacity_is_animating() const {
215    return draw_properties_.screen_space_opacity_is_animating;
216  }
217  bool can_use_lcd_text() const { return draw_properties_.can_use_lcd_text; }
218  bool is_clipped() const { return draw_properties_.is_clipped; }
219  gfx::Rect clip_rect() const { return draw_properties_.clip_rect; }
220  gfx::Rect drawable_content_rect() const {
221    return draw_properties_.drawable_content_rect;
222  }
223  gfx::Rect visible_content_rect() const {
224    return draw_properties_.visible_content_rect;
225  }
226  Layer* render_target() {
227    DCHECK(!draw_properties_.render_target ||
228           draw_properties_.render_target->render_surface());
229    return draw_properties_.render_target;
230  }
231  const Layer* render_target() const {
232    DCHECK(!draw_properties_.render_target ||
233           draw_properties_.render_target->render_surface());
234    return draw_properties_.render_target;
235  }
236  RenderSurface* render_surface() const {
237    return draw_properties_.render_surface.get();
238  }
239  int num_unclipped_descendants() const {
240    return draw_properties_.num_unclipped_descendants;
241  }
242
243  void SetScrollOffset(gfx::Vector2d scroll_offset);
244  gfx::Vector2d scroll_offset() const { return scroll_offset_; }
245  void SetScrollOffsetFromImplSide(gfx::Vector2d scroll_offset);
246
247  void SetMaxScrollOffset(gfx::Vector2d max_scroll_offset);
248  gfx::Vector2d max_scroll_offset() const { return max_scroll_offset_; }
249
250  void SetScrollable(bool scrollable);
251  bool scrollable() const { return scrollable_; }
252
253  void SetShouldScrollOnMainThread(bool should_scroll_on_main_thread);
254  bool should_scroll_on_main_thread() const {
255    return should_scroll_on_main_thread_;
256  }
257
258  void SetHaveWheelEventHandlers(bool have_wheel_event_handlers);
259  bool have_wheel_event_handlers() const { return have_wheel_event_handlers_; }
260
261  void SetNonFastScrollableRegion(const Region& non_fast_scrollable_region);
262  const Region& non_fast_scrollable_region() const {
263    return non_fast_scrollable_region_;
264  }
265
266  void SetTouchEventHandlerRegion(const Region& touch_event_handler_region);
267  const Region& touch_event_handler_region() const {
268    return touch_event_handler_region_;
269  }
270
271  void set_did_scroll_callback(const base::Closure& callback) {
272    did_scroll_callback_ = callback;
273  }
274
275  void SetDrawCheckerboardForMissingTiles(bool checkerboard);
276  bool DrawCheckerboardForMissingTiles() const {
277    return draw_checkerboard_for_missing_tiles_;
278  }
279
280  void SetForceRenderSurface(bool force_render_surface);
281  bool force_render_surface() const { return force_render_surface_; }
282
283  gfx::Vector2d ScrollDelta() const { return gfx::Vector2d(); }
284  gfx::Vector2dF TotalScrollOffset() const {
285    // Floating point to match the LayerImpl version.
286    return scroll_offset() + ScrollDelta();
287  }
288
289  void SetDoubleSided(bool double_sided);
290  bool double_sided() const { return double_sided_; }
291
292  void SetPreserves3d(bool preserves_3d) { preserves_3d_ = preserves_3d; }
293  bool preserves_3d() const { return preserves_3d_; }
294
295  void set_use_parent_backface_visibility(bool use) {
296    use_parent_backface_visibility_ = use;
297  }
298  bool use_parent_backface_visibility() const {
299    return use_parent_backface_visibility_;
300  }
301
302  virtual void SetLayerTreeHost(LayerTreeHost* host);
303
304  bool HasDelegatedContent() const { return false; }
305  bool HasContributingDelegatedRenderPasses() const { return false; }
306
307  void SetIsDrawable(bool is_drawable);
308
309  void SetHideLayerAndSubtree(bool hide);
310  bool hide_layer_and_subtree() const { return hide_layer_and_subtree_; }
311
312  void SetReplicaLayer(Layer* layer);
313  Layer* replica_layer() { return replica_layer_.get(); }
314  const Layer* replica_layer() const { return replica_layer_.get(); }
315
316  bool has_mask() const { return !!mask_layer_.get(); }
317  bool has_replica() const { return !!replica_layer_.get(); }
318  bool replica_has_mask() const {
319    return replica_layer_.get() &&
320           (mask_layer_.get() || replica_layer_->mask_layer_.get());
321  }
322
323  // These methods typically need to be overwritten by derived classes.
324  virtual bool DrawsContent() const;
325  virtual void SavePaintProperties();
326  // Returns true iff any resources were updated that need to be committed.
327  virtual bool Update(ResourceUpdateQueue* queue,
328                      const OcclusionTracker* occlusion);
329  virtual bool NeedMoreUpdates();
330  virtual void SetIsMask(bool is_mask) {}
331  virtual void ReduceMemoryUsage() {}
332
333  virtual std::string DebugName();
334
335  void SetLayerClient(LayerClient* client) { client_ = client; }
336
337  void SetCompositingReasons(CompositingReasons reasons);
338
339  virtual void PushPropertiesTo(LayerImpl* layer);
340
341  void CreateRenderSurface();
342  void ClearRenderSurface();
343
344  // The contents scale converts from logical, non-page-scaled pixels to target
345  // pixels. The contents scale is 1 for the root layer as it is already in
346  // physical pixels. By default contents scale is forced to be 1 except for
347  // subclasses of ContentsScalingLayer.
348  float contents_scale_x() const { return draw_properties_.contents_scale_x; }
349  float contents_scale_y() const { return draw_properties_.contents_scale_y; }
350  gfx::Size content_bounds() const { return draw_properties_.content_bounds; }
351
352  virtual void CalculateContentsScale(float ideal_contents_scale,
353                                      float device_scale_factor,
354                                      float page_scale_factor,
355                                      bool animating_transform_to_screen,
356                                      float* contents_scale_x,
357                                      float* contents_scale_y,
358                                      gfx::Size* content_bounds);
359
360  LayerTreeHost* layer_tree_host() { return layer_tree_host_; }
361  const LayerTreeHost* layer_tree_host() const { return layer_tree_host_; }
362
363  // Set the priority of all desired textures in this layer.
364  virtual void SetTexturePriorities(const PriorityCalculator& priority_calc) {}
365
366  bool AddAnimation(scoped_ptr<Animation> animation);
367  void PauseAnimation(int animation_id, double time_offset);
368  void RemoveAnimation(int animation_id);
369
370  void SuspendAnimations(double monotonic_time);
371  void ResumeAnimations(double monotonic_time);
372
373  bool AnimatedBoundsForBox(const gfx::BoxF& box, gfx::BoxF* bounds) {
374    return layer_animation_controller_->AnimatedBoundsForBox(box, bounds);
375  }
376
377  LayerAnimationController* layer_animation_controller() {
378    return layer_animation_controller_.get();
379  }
380  void SetLayerAnimationControllerForTest(
381      scoped_refptr<LayerAnimationController> controller);
382
383  void set_layer_animation_delegate(AnimationDelegate* delegate) {
384    layer_animation_controller_->set_layer_animation_delegate(delegate);
385  }
386
387  bool HasActiveAnimation() const;
388
389  void AddLayerAnimationEventObserver(
390      LayerAnimationEventObserver* animation_observer);
391  void RemoveLayerAnimationEventObserver(
392      LayerAnimationEventObserver* animation_observer);
393
394  virtual Region VisibleContentOpaqueRegion() const;
395
396  virtual ScrollbarLayerInterface* ToScrollbarLayer();
397
398  gfx::Rect LayerRectToContentRect(const gfx::RectF& layer_rect) const;
399
400  virtual skia::RefPtr<SkPicture> GetPicture() const;
401
402  virtual bool CanClipSelf() const;
403
404  // Constructs a LayerImpl of the correct runtime type for this Layer type.
405  virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl);
406
407  bool NeedsDisplayForTesting() const { return !update_rect_.IsEmpty(); }
408  void ResetNeedsDisplayForTesting() { update_rect_ = gfx::RectF(); }
409
410  RenderingStatsInstrumentation* rendering_stats_instrumentation() const;
411
412  const PaintProperties& paint_properties() const {
413    return paint_properties_;
414  }
415
416  // The scale at which contents should be rastered, to match the scale at
417  // which they will drawn to the screen. This scale is a component of the
418  // contents scale but does not include page/device scale factors.
419  // TODO(danakj): This goes away when TiledLayer goes away.
420  void set_raster_scale(float scale) { raster_scale_ = scale; }
421  float raster_scale() const { return raster_scale_; }
422  bool raster_scale_is_unknown() const { return raster_scale_ == 0.f; }
423
424  virtual bool SupportsLCDText() const;
425
426  bool needs_push_properties() const { return needs_push_properties_; }
427  bool descendant_needs_push_properties() const {
428    return num_dependents_need_push_properties_ > 0;
429  }
430
431 protected:
432  friend class LayerImpl;
433  friend class TreeSynchronizer;
434  virtual ~Layer();
435
436  Layer();
437
438  // These SetNeeds functions are in order of severity of update:
439  //
440  // Called when this layer has been modified in some way, but isn't sure
441  // that it needs a commit yet.  It needs CalcDrawProperties and UpdateLayers
442  // before it knows whether or not a commit is required.
443  void SetNeedsUpdate();
444  // Called when a property has been modified in a way that the layer
445  // knows immediately that a commit is required.  This implies SetNeedsUpdate
446  // as well as SetNeedsPushProperties to push that property.
447  void SetNeedsCommit();
448  // Called when there's been a change in layer structure.  Implies both
449  // SetNeedsUpdate and SetNeedsCommit, but not SetNeedsPushProperties.
450  void SetNeedsFullTreeSync();
451
452  // Called when the next commit should wait until the pending tree is activated
453  // before finishing the commit and unblocking the main thread. Used to ensure
454  // unused resources on the impl thread are returned before commit completes.
455  void SetNextCommitWaitsForActivation();
456
457  void SetNeedsPushProperties();
458  void AddDependentNeedsPushProperties();
459  void RemoveDependentNeedsPushProperties();
460  bool parent_should_know_need_push_properties() const {
461    return needs_push_properties() || descendant_needs_push_properties();
462  }
463
464  bool IsPropertyChangeAllowed() const;
465
466  // If this layer has a scroll parent, it removes |this| from its list of
467  // scroll children.
468  void RemoveFromScrollTree();
469
470  // If this layer has a clip parent, it removes |this| from its list of clip
471  // children.
472  void RemoveFromClipTree();
473
474  void reset_raster_scale_to_unknown() { raster_scale_ = 0.f; }
475
476  // This flag is set when the layer needs to push properties to the impl
477  // side.
478  bool needs_push_properties_;
479
480  // The number of direct children or dependent layers that need to be recursed
481  // to in order for them or a descendent of them to push properties to the impl
482  // side.
483  int num_dependents_need_push_properties_;
484
485  // Tracks whether this layer may have changed stacking order with its
486  // siblings.
487  bool stacking_order_changed_;
488
489  // The update rect is the region of the compositor resource that was
490  // actually updated by the compositor. For layers that may do updating
491  // outside the compositor's control (i.e. plugin layers), this information
492  // is not available and the update rect will remain empty.
493  // Note this rect is in layer space (not content space).
494  gfx::RectF update_rect_;
495
496  scoped_refptr<Layer> mask_layer_;
497
498  int layer_id_;
499
500  // When true, the layer is about to perform an update. Any commit requests
501  // will be handled implicitly after the update completes.
502  bool ignore_set_needs_commit_;
503
504 private:
505  friend class base::RefCounted<Layer>;
506
507  void SetParent(Layer* layer);
508  bool DescendantIsFixedToContainerLayer() const;
509
510  // Returns the index of the child or -1 if not found.
511  int IndexOfChild(const Layer* reference);
512
513  // This should only be called from RemoveFromParent().
514  void RemoveChildOrDependent(Layer* child);
515
516  // LayerAnimationValueObserver implementation.
517  virtual void OnOpacityAnimated(float opacity) OVERRIDE;
518  virtual void OnTransformAnimated(const gfx::Transform& transform) OVERRIDE;
519  virtual bool IsActive() const OVERRIDE;
520
521  LayerList children_;
522  Layer* parent_;
523
524  // Layer instances have a weak pointer to their LayerTreeHost.
525  // This pointer value is nil when a Layer is not in a tree and is
526  // updated via SetLayerTreeHost() if a layer moves between trees.
527  LayerTreeHost* layer_tree_host_;
528
529  scoped_refptr<LayerAnimationController> layer_animation_controller_;
530
531  // Layer properties.
532  gfx::Size bounds_;
533
534  gfx::Vector2d scroll_offset_;
535  gfx::Vector2d max_scroll_offset_;
536  bool scrollable_;
537  bool should_scroll_on_main_thread_;
538  bool have_wheel_event_handlers_;
539  Region non_fast_scrollable_region_;
540  Region touch_event_handler_region_;
541  gfx::PointF position_;
542  gfx::PointF anchor_point_;
543  SkColor background_color_;
544  CompositingReasons compositing_reasons_;
545  float opacity_;
546  skia::RefPtr<SkImageFilter> filter_;
547  FilterOperations filters_;
548  FilterOperations background_filters_;
549  float anchor_point_z_;
550  bool is_container_for_fixed_position_layers_;
551  LayerPositionConstraint position_constraint_;
552  bool is_drawable_;
553  bool hide_layer_and_subtree_;
554  bool masks_to_bounds_;
555  bool contents_opaque_;
556  bool double_sided_;
557  bool preserves_3d_;
558  bool use_parent_backface_visibility_;
559  bool draw_checkerboard_for_missing_tiles_;
560  bool force_render_surface_;
561  Layer* scroll_parent_;
562  scoped_ptr<std::set<Layer*> > scroll_children_;
563
564  Layer* clip_parent_;
565  scoped_ptr<std::set<Layer*> > clip_children_;
566
567  gfx::Transform transform_;
568  gfx::Transform sublayer_transform_;
569
570  // Replica layer used for reflections.
571  scoped_refptr<Layer> replica_layer_;
572
573  // Transient properties.
574  float raster_scale_;
575
576  LayerClient* client_;
577
578  ScopedPtrVector<CopyOutputRequest> copy_requests_;
579
580  base::Closure did_scroll_callback_;
581
582  DrawProperties<Layer, RenderSurface> draw_properties_;
583
584  PaintProperties paint_properties_;
585
586  DISALLOW_COPY_AND_ASSIGN(Layer);
587};
588
589}  // namespace cc
590
591#endif  // CC_LAYERS_LAYER_H_
592